1. Field of the Invention
The present invention relates generally to forage harvesters and, more particularly, is concerned with improvements therein which facilitate easy access to the shearbar on the forage harvester for servicing and maintenance purposes.
2. Description of the Prior Art
In order to maintain the operating efficiency of a forage harvester of the type having a rotatable cutterhead with knives spaced about the periphery thereof and an adjacently-positioned, stationary shearbar cooperable with the cutterhead knives to comminute crop material, it is necessary to maintain a desired uniform clearance between the shearbar and the cutterhead knives, such as from 0.010 to 0.015 inch, as the knives move pass the shearbar upon rotation of the cutterhead. Therefore, during the harvesting season, the clearance between the shearbar and the cutterhead knives must be guaged on a regular, periodic basis by the operator and adjustment of the shearbar made when needed. Otherwise, if the clearance is not checked closely and non-uniformity thereof occurs, the result will be non-uniformity or uneveness in the length of cut of the crop material being comminuted from one end of the cutterhead to the other which will cause greater power consumption and more fuel usage in the operation of the forage harvester.
Such forage harvesters also include tandemly-arranged front and rear points of upper and lower feed rolls located forwardly of the cutterhead and shearbar. The lower rear roll has a smooth outer cylindrical surface and a scraper is mounted adjacent to and forwardly of the scraper for cleaning the surface of the smooth lower rear roll. As in the case of the shearbar, it is necessary to maintain proper clearance between the scraper and the smooth lower roll in order to prevent buildup of crop material residue on it which would adversely affect the operating efficiency of the forage harvester.
It is therefore highly desirable to make the shearbar and cutterhead area and the scraper and lower rear feed roll area of the forage harvester readily accessible so that it will be convenient for the operator to give close attention to the shearbar/cutterhead and scraper/roll clearances on a regular basis. However, most of the forage harvesters heretofore have not offered a convenient, simple or easy method of gaining quick access to one or both of these areas for such servicing and maintenance purposes.
One method currently being utilized on commercial forage harvesters is to provide a small door on one side of the cutterhead housing adjacent the shearbar/scraper mount which may be opened and a feeler guage then inserted by the operator to check the clearance between the shearbar and the cutterhead knives and between the scraper and the smooth feed roll. However, such method allows little visual contact by the operator with the area being guaged and limits full reach of the feeler guage across the total width of the shearbar. Instead, the operator must rely mostly on his blind feel with the guage. As a result, operators will have a tendency to neglect making frequent adjustments to the shearbar and scraper clearances due to the difficulty in carrying through on the checking procedure.
Another current method is to provide the upper feed rolls mounted to an upper transition and spout assembly, all of which may be pivoted as a unit rearwardly and away from the remainder of the housing so that the cutterhead, shearbar, scraper and smooth feed roll are exposed from above. Although this method provides greater accessibility to the shearbar and scraper areas by the operator once the unit has been pivoted out of the way, the transition and spout assembly is somewhat bulky and heavy and thus is difficult and awkward to lift and pivot. As a result, operators will likewise with this method have a tendency to put off making frequent adjustments to the shearbar and scraper clearances since it is just not a simple and quick solution to the problem of shearbar/scraper accessibility.